• 제목/요약/키워드: Engineering process

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역정규 손실함수를 이용한 다변량 공정능력지수 (Multivariate Process Capability Index Using Inverted Normal Loss Function)

  • 문혜진;정영배
    • 산업경영시스템학회지
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    • 제41권2호
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    • pp.174-183
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    • 2018
  • In the industrial fields, the process capability index has been using to evaluate the variation of quality in the process. The traditional process capability indices such as $C_p$, $C_{pk}$, $C_{pm}$ and $C^+_{pm}$ have been applied in the industrial fields. These traditional process capability indices are mainly applied in the univariate analysis. However, the main streams in the recent industry are the multivariate manufacturing process and the multiple quality characteristics are corrected each other. Therefore, the multivariate statistical method should be used in the process capability analysis. The multivariate process indices need to be enhanced with more useful information and extensive application in the recent industrial fields. Hence, the purpose of the study is to develop a more effective multivariate process index ($MC_{pI}$) using the multivariate inverted normal loss function. The multivariate inverted normal loss function has the flexibility for the any type of the symmetrical and asymmetrical loss functions as well as the economic information. Especially, the proposed modeling method for the multivariate inverted normal loss function (MINLF) and the expected loss from MINLF in this paper can be applied to the any type of the symmetrical and asymmetrical loss functions. And this modeling method can be easily expanded from a bivariate case to a multivariate case.

드릴링 공정의 전단 및 마찰 특성 해석 (Analyses of Shear and Frictional Characteristics in Drilling Process)

  • 김선일;최원식;손재환;장은숙;이영문
    • 한국기계가공학회지
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    • 제11권6호
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    • pp.22-27
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    • 2012
  • Drilling process is usually the most efficient and economical method of making a hole in a solid body. However, there have been no analytical method to assess drilling process based on the shear and frictional characteristics. In this paper, procedures for analyzing shear and frictional processes of drilling have been established by adopting an equivalent turning system to drilling. A series of drilling experiments were carried out with varying feed, velocity and drill shape factors. Using the results of the experiments, the cutting characteristics including shear in the primary shear zone and friction in the chip-tool contact region of drilling process have been analyzed. The specific cutting energy tends to decrease exponentially with increase of feed rate. In drilling process 35-40% of the total energy is consumed in the friction process. This is greater than that of turning process in cutting of the same work material.

Process Evaluation Model based on Goal-Scenario for Business Activity Monitoring

  • Baek, Su-Jin;Song, Young-Jae
    • Journal of information and communication convergence engineering
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    • 제9권4호
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    • pp.379-384
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    • 2011
  • The scope of the problems that could be solved by monitoring and the improvement of the recognition time is directly correlated to the performance of the management function of the business process. However, the current monitoring process of business activities decides whether to apply warnings or not by assuming a fixed environment and showing expressions based on the design rules. Also, warnings are applied by carrying out the measuring process when the event attribute values are inserted at every point. Therefore, there is a limit for distinguishing the range of occurrence and the level of severity in regard to the new external problems occurring in a complicated environment. Such problems cannot be ed. Also, since it is difficult to expand the range of problems which can be possibly evaluated, it is impossible to evaluate any unexpected situation which could occur in the execution period. In this paper, a process-evaluating model based on the goal scenario is suggested to provide constant services through the current monitoring process in regard to the service demands of the new scenario which occurs outside. The new demands based on the outside situation are analyzed according to the goal scenario for the process activities. Also, by using the meta-heuristic algorithm, a similar process model is found and identified by combining similarity and interrelationship. The process can be stopped in advance or adjusted to the wanted direction.

FNR process를 이용한 하수처리장의 질소.인의 제거에 관한 연구 (A Study on Nitrogen and Phosphorus Removal in FNR Process)

  • 조일형;이내현;이승목;김영규
    • 한국환경과학회지
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    • 제15권6호
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    • pp.571-577
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    • 2006
  • This study make a comparison between the phosphorus removal performance of FNR(Ferrous Nutrient Removal) process and A/O process by the laboratory experiments. For simultaneous removal of phosphorus, iron electrolysis was combined with oxic tank. Iron precipitation reactor on the electrochemical behaviors of phosphorus in the iron bed. The phosphorus removal in FNR process was more than A/O process. Iron salts produced by iron electrolysis might help to remove COD and nitrogen. And the demanded longer SRT is the more removes the removes COD, nitrogen, and phosphorus. Also, FNR process of sludge quantity more reduce than A/O process to input cohesive agents.

프로세스 구조 제약조건과 사회적 관계를 이용한 비즈니스 프로세스 모델링 방법론 (Business Process Modeling using Process Structural Constraints and Social Relations)

  • 유영웅;김승;배혜림
    • 산업공학
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    • 제25권3호
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    • pp.300-308
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    • 2012
  • For convenient business process modeling we propose a mathematical approach to obtain appropriate process structures. In this paper, we define business process structural constraints, on which basis, using Social Network Analysis (SNA), we analyze the frequency of handover occurrences among performers in social network. We here present, therefrom, a new, mathematical approach to business process modeling that proceeds by identifying the social relations among activities.

국내 BIM 교육과정 분석을 통한 건축공학 설계교육 프로세스 개선 (Improvement of architectural engineering design education process through an analysis of BIM courses)

  • 강다영;신규철
    • 한국건축시공학회지
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    • 제10권3호
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    • pp.145-153
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    • 2010
  • BIM은 최근 공공 및 민간 발주자에 의해 활용이 점차 확대 시행 되고 있으며, 설계사무실에서도 BIM을 도입하고자 하고 있다. 이런 흐름에 발맞추어 학부교육에서 BIM의 교육이 필요함을 인지하고, 현재 진행되고 있는 국내 BIM 교육의 현황을 파악하여 학부교육에서 이루어질 수 있는 설계교육 프로세스의 개선을 도출하고자 하였다. 기존에 건축공학 교육과정에 BIM을 활용하여 구조, 시공, 설비의 각 요소의 핵심이 반영된 종합적인 설계가 가능하게 하고자 한다. 3D 중심의 설계를 통하여 구조설계교육을 강화하고 BIM 도구를 활용하여 공정 및 적산을 연계한 시공 CM교육을 강화하고 친환경 사전분석을 통해 친환경설계 교육을 이루도록 설계교육 프로세스를 개선하고자 한다.

신경망과 유전 알고리즘을 이용한 광소자용 ZnO 박막 특성 공정 모델링 및 최적화 (Process Modeling and Optimization for Characteristics of ZnO Thin Films using Neural Networks and Genetic Algorithms)

  • 고영돈;강홍성;정민창;이상렬;명재민;윤일구
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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    • pp.33-36
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    • 2004
  • The process modeling for the growth rate in pulsed laser deposition(PLD)-grown ZnO thin films is investigated using neural networks(NNets) and the process recipes is optimized via genetic algorithms(GAs). D-optimal design is carried out and the growth rate is characterized by NNets based on the back-propagation(BP) algorithm. GAs is then used to search the desired recipes for the desired growth rate. The statistical analysis is used to verify the fitness of the nonlinear process model. This process modeling and optimization algorithms can explain the characteristics of the desired responses varying with process conditions.

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INTEGRATION MODEL OF COST AND SCHEDULE IN STEEL BOX GIRDER BRIDGE PRODUCTION PROCESS

  • Seok Kim;Kyoungmin Kim;Seung-Ho Ha ;Kyong Ju Kim
    • 국제학술발표논문집
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    • The 1th International Conference on Construction Engineering and Project Management
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    • pp.1262-1267
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    • 2005
  • It is still difficult to share and utilize the information generated at each phase of a steel box girder production process due to the spatial gap and different level of management information. The physical distance results in the inefficiency of the information transmission, the accidental omission and typos of the relative information, and so on. Various levels of management information make it difficult to embody a new management system. Eventually, these factors incur the loss of cost and schedule and interrupt development of a new management system. This paper analyzes a current process and presents graphical process flow by using IDEF0. Based this analysis, the research for new production process and work breakdown structure (WBS) is conducted. At the end of this paper, the conceptual design of this system is suggested. Through new management system, it is expected that the model proposed in this study will improve the management process in the steel box production, and the improved process will reduce the redundant cost and schedule information, transmission and deposit generated by manual paper.

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Development of Ultral Clean Machining Technology with Electrolytic Polishing Process

  • Lee, Eun-Sang;Park, Jeong--Woo;Moon, Young-Hun
    • International Journal of Precision Engineering and Manufacturing
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    • 제2권1호
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    • pp.18-25
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    • 2001
  • Electrolytic polishing is the anodic dissolution process in the transpassive state. It removes non-metallic inclusion and improves mechanical and corrosion resistance of stainless steel. If there is a Bailby layer, it will be removed and the true structure of the surface will be restored. Electrolytic polishing is normally used to remove a very thin layer of material from the surface of metal object. A new electrolyte composed of phosphoric, sulfuric and distilled water has been developed in this study. Two current density, high & low current density regions, have been applied in this study. In this study, In the region of high current density, there is no plateau region but excellent electrolytic polishing effect can be accomplished in short machining time because material removel process and leveling process occur simultaneously. In the low current density region, there can be found plateau region. The material removal process and leveling process occur successively. The aim of this work is to determine electrolytic polishing for stainless steel in terms of high & low current density and workpiece surface roughness.

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용융잉크 적층공정을 이용한 내부채색형상을 포함한 광조형물 제작에 관한 연구 (A Study on Fabrication of Internally Colored Shape in Stereolithography Parts using Molten Ink Deposition Process)

  • 박종철;박석희;강상일;양동열
    • 한국정밀공학회지
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    • 제27권6호
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    • pp.98-104
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    • 2010
  • Rapid Prototypes with internally colored objects are convenient by visualizing. A rapid prototyping method has been developed to fabricate mono-colored or multi-colored objects. In this work, a new process was proposed that can fabricate internally visible colored 3D objects in stereolithography parts. The process consists of projection stereolithography process using transparent photocurable resin for outer shapes and molten ink deposition process using molten solid ink for internal shapes. In molten ink deposition process, molten solid ink could be deposited uniformly in a designed pattern. To make molten solid ink uniform over a designed region, parametric study through a patterning solid ink was performed. By laminating resin and solid ink in sequence, the process can make colored 3D objects in StereoLithography(SL) parts. The practicality and effectiveness of the proposed process were verified through fabrication of colored basic 3D objects in SL parts.